user/settings: fix bad error handle of leave organization

routers/user/setting.go

@@ -442,12 +442,14 @@ func SettingsOrganizations(ctx *context.Context) {
 
 func SettingsLeaveOrganization(ctx *context.Context) {
 	err := models.RemoveOrgUser(ctx.QueryInt64("id"), ctx.User.ID)
+	if err != nil {
 		if models.IsErrLastOrgOwner(err) {
 			ctx.Flash.Error(ctx.Tr("form.last_org_owner"))
 		} else {
 			ctx.Handle(500, "RemoveOrgUser", err)
 			return
 		}
+	}
 
 	ctx.JSON(200, map[string]interface{}{
 		"redirect": setting.AppSubUrl + "/user/settings/organizations",